patch 8.2.4973: Vim9: type error for list unpack mentions argument

Problem:    Vim9: type error for list unpack mentions argument.
Solution:   Mention variable. (close #10435)
diff --git a/src/testdir/test_vim9_disassemble.vim b/src/testdir/test_vim9_disassemble.vim
index 3ab3c0d..c99c8b4 100644
--- a/src/testdir/test_vim9_disassemble.vim
+++ b/src/testdir/test_vim9_disassemble.vim
@@ -581,10 +581,10 @@
         '\d CHECKTYPE list<any> stack\[-1\]\_s*' ..
         '\d CHECKLEN >= 2\_s*' ..
         '\d\+ ITEM 0\_s*' ..
-        '\d\+ CHECKTYPE string stack\[-1\] arg 1\_s*' ..
+        '\d\+ CHECKTYPE string stack\[-1\] var 1\_s*' ..
         '\d\+ STORE $0\_s*' ..
         '\d\+ ITEM 1\_s*' ..
-        '\d\+ CHECKTYPE string stack\[-1\] arg 2\_s*' ..
+        '\d\+ CHECKTYPE string stack\[-1\] var 2\_s*' ..
         '\d\+ STORE $1\_s*' ..
         '\d\+ SLICE 2\_s*' ..
         '\d\+ STORE $2\_s*' ..
diff --git a/src/testdir/test_vim9_script.vim b/src/testdir/test_vim9_script.vim
index 7166b13..fc0ef15 100644
--- a/src/testdir/test_vim9_script.vim
+++ b/src/testdir/test_vim9_script.vim
@@ -2302,7 +2302,7 @@
         echo k v
       endfor
   END
-  v9.CheckDefExecAndScriptFailure(lines, ['E1013: Argument 1: type mismatch, expected job but got string', 'E1012: Type mismatch; expected job but got string'], 2)
+  v9.CheckDefExecAndScriptFailure(lines, ['E1163: Variable 1: type mismatch, expected job but got string', 'E1012: Type mismatch; expected job but got string'], 2)
 
   lines =<< trim END
       var i = 0